1 /*
2 * Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 // no precompiled headers
26 #include "asm/macroAssembler.hpp"
27 #include "classfile/classLoader.hpp"
28 #include "classfile/systemDictionary.hpp"
29 #include "classfile/vmSymbols.hpp"
30 #include "code/icBuffer.hpp"
31 #include "code/vtableStubs.hpp"
32 #include "interpreter/interpreter.hpp"
33 #include "jvm_linux.h"
34 #include "memory/allocation.inline.hpp"
35 #include "mutex_linux.inline.hpp"
36 #include "nativeInst_sparc.hpp"
37 #include "os_share_linux.hpp"
38 #include "prims/jniFastGetField.hpp"
39 #include "prims/jvm.h"
40 #include "prims/jvm_misc.hpp"
41 #include "runtime/arguments.hpp"
42 #include "runtime/extendedPC.hpp"
43 #include "runtime/frame.inline.hpp"
44 #include "runtime/interfaceSupport.hpp"
45 #include "runtime/java.hpp"
46 #include "runtime/javaCalls.hpp"
47 #include "runtime/mutexLocker.hpp"
48 #include "runtime/osThread.hpp"
49 #include "runtime/sharedRuntime.hpp"
50 #include "runtime/stubRoutines.hpp"
51 #include "runtime/thread.inline.hpp"
52 #include "runtime/timer.hpp"
53 #include "utilities/events.hpp"
54 #include "utilities/vmError.hpp"
55
56 // Linux/Sparc has rather obscure naming of registers in sigcontext
57 // different between 32 and 64 bits
58 #ifdef _LP64
59 #define SIG_PC(x) ((x)->sigc_regs.tpc)
60 #define SIG_NPC(x) ((x)->sigc_regs.tnpc)
61 #define SIG_REGS(x) ((x)->sigc_regs)
62 #else
63 #define SIG_PC(x) ((x)->si_regs.pc)
64 #define SIG_NPC(x) ((x)->si_regs.npc)
65 #define SIG_REGS(x) ((x)->si_regs)
66 #endif
67
68 // those are to reference registers in sigcontext
69 enum {
70 CON_G0 = 0,
71 CON_G1,
72 CON_G2,
73 CON_G3,
74 CON_G4,
75 CON_G5,
76 CON_G6,
77 CON_G7,
78 CON_O0,
79 CON_O1,
80 CON_O2,
81 CON_O3,
82 CON_O4,
83 CON_O5,
84 CON_O6,
85 CON_O7,
86 };
87
88 static inline void set_cont_address(sigcontext* ctx, address addr) {
89 SIG_PC(ctx) = (intptr_t)addr;
90 SIG_NPC(ctx) = (intptr_t)(addr+4);
91 }
92
93 // For Forte Analyzer AsyncGetCallTrace profiling support - thread is
94 // currently interrupted by SIGPROF.
95 // os::Solaris::fetch_frame_from_ucontext() tries to skip nested
96 // signal frames. Currently we don't do that on Linux, so it's the
97 // same as os::fetch_frame_from_context().
98 ExtendedPC os::Linux::fetch_frame_from_ucontext(Thread* thread,
99 ucontext_t* uc,
100 intptr_t** ret_sp,
101 intptr_t** ret_fp) {
102 assert(thread != NULL, "just checking");
103 assert(ret_sp != NULL, "just checking");
104 assert(ret_fp != NULL, "just checking");
105
106 return os::fetch_frame_from_context(uc, ret_sp, ret_fp);
107 }
108
109 ExtendedPC os::fetch_frame_from_context(void* ucVoid,
110 intptr_t** ret_sp,
111 intptr_t** ret_fp) {
112 ucontext_t* uc = (ucontext_t*) ucVoid;
113 ExtendedPC epc;
114
115 if (uc != NULL) {
116 epc = ExtendedPC(os::Linux::ucontext_get_pc(uc));
117 if (ret_sp) {
118 *ret_sp = os::Linux::ucontext_get_sp(uc);
119 }
120 if (ret_fp) {
121 *ret_fp = (intptr_t*)NULL;
122 }
123 } else {
124 // construct empty ExtendedPC for return value checking
125 epc = ExtendedPC(NULL);
126 if (ret_sp) {
127 *ret_sp = (intptr_t*) NULL;
128 }
129 if (ret_fp) {
130 *ret_fp = (intptr_t*) NULL;
131 }
132 }
133
134 return epc;
135 }
136
137 frame os::fetch_frame_from_context(void* ucVoid) {
138 intptr_t* sp;
139 ExtendedPC epc = fetch_frame_from_context(ucVoid, &sp, NULL);
140 return frame(sp, frame::unpatchable, epc.pc());
141 }
142
143 frame os::get_sender_for_C_frame(frame* fr) {
144 return frame(fr->sender_sp(), fr->link(), fr->sender_pc());
145 }
146
147 frame os::current_frame() {
148 fprintf(stderr, "current_frame()");
149
150 intptr_t* sp = StubRoutines::Sparc::flush_callers_register_windows_func()();
151 frame myframe(sp, frame::unpatchable,
152 CAST_FROM_FN_PTR(address, os::current_frame));
153 if (os::is_first_C_frame(&myframe)) {
154 // stack is not walkable
155 return frame(NULL, frame::unpatchable, NULL);
156 } else {
157 return os::get_sender_for_C_frame(&myframe);
158 }
159 }
160
161 address os::current_stack_pointer() {
162 register void *sp __asm__ ("sp");
163 return (address)sp;
164 }
165
166 static void current_stack_region(address* bottom, size_t* size) {
167 if (os::Linux::is_initial_thread()) {
168 // initial thread needs special handling because pthread_getattr_np()
169 // may return bogus value.
170 *bottom = os::Linux::initial_thread_stack_bottom();
171 *size = os::Linux::initial_thread_stack_size();
172 } else {
173 pthread_attr_t attr;
174
175 int rslt = pthread_getattr_np(pthread_self(), &attr);
176
177 // JVM needs to know exact stack location, abort if it fails
178 if (rslt != 0) {
179 if (rslt == ENOMEM) {
180 vm_exit_out_of_memory(0, OOM_MMAP_ERROR, "pthread_getattr_np");
181 } else {
182 fatal(err_msg("pthread_getattr_np failed with errno = %d", rslt));
183 }
184 }
185
186 if (pthread_attr_getstack(&attr, (void**)bottom, size) != 0) {
187 fatal("Can not locate current stack attributes!");
188 }
189
190 pthread_attr_destroy(&attr);
191 }
192 assert(os::current_stack_pointer() >= *bottom &&
193 os::current_stack_pointer() < *bottom + *size, "just checking");
194 }
195
196 address os::current_stack_base() {
197 address bottom;
198 size_t size;
199 current_stack_region(&bottom, &size);
200 return bottom + size;
201 }
202
203 size_t os::current_stack_size() {
204 // stack size includes normal stack and HotSpot guard pages
205 address bottom;
206 size_t size;
207 current_stack_region(&bottom, &size);
208 return size;
209 }
210
211 char* os::non_memory_address_word() {
212 // Must never look like an address returned by reserve_memory,
213 // even in its subfields (as defined by the CPU immediate fields,
214 // if the CPU splits constants across multiple instructions).
215 // On SPARC, 0 != %hi(any real address), because there is no
216 // allocation in the first 1Kb of the virtual address space.
217 return (char*) 0;
218 }
219
220 void os::initialize_thread(Thread* thr) {}
221
222 void os::print_context(outputStream *st, void *context) {
223 if (context == NULL) return;
224
225 ucontext_t* uc = (ucontext_t*)context;
226 sigcontext* sc = (sigcontext*)context;
227 st->print_cr("Registers:");
228
229 st->print_cr(" G1=" INTPTR_FORMAT " G2=" INTPTR_FORMAT
230 " G3=" INTPTR_FORMAT " G4=" INTPTR_FORMAT,
231 SIG_REGS(sc).u_regs[CON_G1],
232 SIG_REGS(sc).u_regs[CON_G2],
233 SIG_REGS(sc).u_regs[CON_G3],
234 SIG_REGS(sc).u_regs[CON_G4]);
235 st->print_cr(" G5=" INTPTR_FORMAT " G6=" INTPTR_FORMAT
236 " G7=" INTPTR_FORMAT " Y=0x%x",
237 SIG_REGS(sc).u_regs[CON_G5],
238 SIG_REGS(sc).u_regs[CON_G6],
239 SIG_REGS(sc).u_regs[CON_G7],
240 SIG_REGS(sc).y);
241 st->print_cr(" O0=" INTPTR_FORMAT " O1=" INTPTR_FORMAT
242 " O2=" INTPTR_FORMAT " O3=" INTPTR_FORMAT,
243 SIG_REGS(sc).u_regs[CON_O0],
244 SIG_REGS(sc).u_regs[CON_O1],
245 SIG_REGS(sc).u_regs[CON_O2],
246 SIG_REGS(sc).u_regs[CON_O3]);
247 st->print_cr(" O4=" INTPTR_FORMAT " O5=" INTPTR_FORMAT
248 " O6=" INTPTR_FORMAT " O7=" INTPTR_FORMAT,
249 SIG_REGS(sc).u_regs[CON_O4],
250 SIG_REGS(sc).u_regs[CON_O5],
251 SIG_REGS(sc).u_regs[CON_O6],
252 SIG_REGS(sc).u_regs[CON_O7]);
253
254
255 intptr_t *sp = (intptr_t *)os::Linux::ucontext_get_sp(uc);
256 st->print_cr(" L0=" INTPTR_FORMAT " L1=" INTPTR_FORMAT
257 " L2=" INTPTR_FORMAT " L3=" INTPTR_FORMAT,
258 sp[L0->sp_offset_in_saved_window()],
259 sp[L1->sp_offset_in_saved_window()],
260 sp[L2->sp_offset_in_saved_window()],
261 sp[L3->sp_offset_in_saved_window()]);
262 st->print_cr(" L4=" INTPTR_FORMAT " L5=" INTPTR_FORMAT
263 " L6=" INTPTR_FORMAT " L7=" INTPTR_FORMAT,
264 sp[L4->sp_offset_in_saved_window()],
265 sp[L5->sp_offset_in_saved_window()],
266 sp[L6->sp_offset_in_saved_window()],
267 sp[L7->sp_offset_in_saved_window()]);
268 st->print_cr(" I0=" INTPTR_FORMAT " I1=" INTPTR_FORMAT
269 " I2=" INTPTR_FORMAT " I3=" INTPTR_FORMAT,
270 sp[I0->sp_offset_in_saved_window()],
271 sp[I1->sp_offset_in_saved_window()],
272 sp[I2->sp_offset_in_saved_window()],
273 sp[I3->sp_offset_in_saved_window()]);
274 st->print_cr(" I4=" INTPTR_FORMAT " I5=" INTPTR_FORMAT
275 " I6=" INTPTR_FORMAT " I7=" INTPTR_FORMAT,
276 sp[I4->sp_offset_in_saved_window()],
277 sp[I5->sp_offset_in_saved_window()],
278 sp[I6->sp_offset_in_saved_window()],
279 sp[I7->sp_offset_in_saved_window()]);
280
281 st->print_cr(" PC=" INTPTR_FORMAT " nPC=" INTPTR_FORMAT,
282 SIG_PC(sc),
283 SIG_NPC(sc));
284 st->cr();
285 st->cr();
286
287 st->print_cr("Top of Stack: (sp=" INTPTR_FORMAT ")", p2i(sp));
288 print_hex_dump(st, (address)sp, (address)(sp + 32), sizeof(intptr_t));
289 st->cr();
290
291 // Note: it may be unsafe to inspect memory near pc. For example, pc may
292 // point to garbage if entry point in an nmethod is corrupted. Leave
293 // this at the end, and hope for the best.
294 address pc = os::Linux::ucontext_get_pc(uc);
295 st->print_cr("Instructions: (pc=" INTPTR_FORMAT ")", p2i(pc));
296 print_hex_dump(st, pc - 32, pc + 32, sizeof(char));
297 }
298
299
300 void os::print_register_info(outputStream *st, void *context) {
301 if (context == NULL) return;
302
303 ucontext_t *uc = (ucontext_t*)context;
304 sigcontext* sc = (sigcontext*)context;
305 intptr_t *sp = (intptr_t *)os::Linux::ucontext_get_sp(uc);
306
307 st->print_cr("Register to memory mapping:");
308 st->cr();
309
310 // this is only for the "general purpose" registers
311 st->print("G1="); print_location(st, SIG_REGS(sc).u_regs[CON_G1]);
312 st->print("G2="); print_location(st, SIG_REGS(sc).u_regs[CON_G2]);
313 st->print("G3="); print_location(st, SIG_REGS(sc).u_regs[CON_G3]);
314 st->print("G4="); print_location(st, SIG_REGS(sc).u_regs[CON_G4]);
315 st->print("G5="); print_location(st, SIG_REGS(sc).u_regs[CON_G5]);
316 st->print("G6="); print_location(st, SIG_REGS(sc).u_regs[CON_G6]);
317 st->print("G7="); print_location(st, SIG_REGS(sc).u_regs[CON_G7]);
318 st->cr();
319
320 st->print("O0="); print_location(st, SIG_REGS(sc).u_regs[CON_O0]);
321 st->print("O1="); print_location(st, SIG_REGS(sc).u_regs[CON_O1]);
322 st->print("O2="); print_location(st, SIG_REGS(sc).u_regs[CON_O2]);
323 st->print("O3="); print_location(st, SIG_REGS(sc).u_regs[CON_O3]);
324 st->print("O4="); print_location(st, SIG_REGS(sc).u_regs[CON_O4]);
325 st->print("O5="); print_location(st, SIG_REGS(sc).u_regs[CON_O5]);
326 st->print("O6="); print_location(st, SIG_REGS(sc).u_regs[CON_O6]);
327 st->print("O7="); print_location(st, SIG_REGS(sc).u_regs[CON_O7]);
328 st->cr();
329
330 st->print("L0="); print_location(st, sp[L0->sp_offset_in_saved_window()]);
331 st->print("L1="); print_location(st, sp[L1->sp_offset_in_saved_window()]);
332 st->print("L2="); print_location(st, sp[L2->sp_offset_in_saved_window()]);
333 st->print("L3="); print_location(st, sp[L3->sp_offset_in_saved_window()]);
334 st->print("L4="); print_location(st, sp[L4->sp_offset_in_saved_window()]);
335 st->print("L5="); print_location(st, sp[L5->sp_offset_in_saved_window()]);
336 st->print("L6="); print_location(st, sp[L6->sp_offset_in_saved_window()]);
337 st->print("L7="); print_location(st, sp[L7->sp_offset_in_saved_window()]);
338 st->cr();
339
340 st->print("I0="); print_location(st, sp[I0->sp_offset_in_saved_window()]);
341 st->print("I1="); print_location(st, sp[I1->sp_offset_in_saved_window()]);
342 st->print("I2="); print_location(st, sp[I2->sp_offset_in_saved_window()]);
343 st->print("I3="); print_location(st, sp[I3->sp_offset_in_saved_window()]);
344 st->print("I4="); print_location(st, sp[I4->sp_offset_in_saved_window()]);
345 st->print("I5="); print_location(st, sp[I5->sp_offset_in_saved_window()]);
346 st->print("I6="); print_location(st, sp[I6->sp_offset_in_saved_window()]);
347 st->print("I7="); print_location(st, sp[I7->sp_offset_in_saved_window()]);
348 st->cr();
349 }
350
351
352 address os::Linux::ucontext_get_pc(ucontext_t* uc) {
353 return (address) SIG_PC((sigcontext*)uc);
354 }
355
356 intptr_t* os::Linux::ucontext_get_sp(ucontext_t *uc) {
357 return (intptr_t*)
358 ((intptr_t)SIG_REGS((sigcontext*)uc).u_regs[CON_O6] + STACK_BIAS);
359 }
360
361 // not used on Sparc
362 intptr_t* os::Linux::ucontext_get_fp(ucontext_t *uc) {
363 ShouldNotReachHere();
364 return NULL;
365 }
366
367 // Utility functions
368
369 inline static bool checkPrefetch(sigcontext* uc, address pc) {
370 if (StubRoutines::is_safefetch_fault(pc)) {
371 set_cont_address(uc, address(StubRoutines::continuation_for_safefetch_fault(pc)));
372 return true;
373 }
374 return false;
375 }
376
377 inline static bool checkOverflow(sigcontext* uc,
378 address pc,
379 address addr,
380 JavaThread* thread,
381 address* stub) {
382 // check if fault address is within thread stack
383 if (addr < thread->stack_base() &&
384 addr >= thread->stack_base() - thread->stack_size()) {
385 // stack overflow
386 if (thread->in_stack_yellow_zone(addr)) {
387 thread->disable_stack_yellow_zone();
388 if (thread->thread_state() == _thread_in_Java) {
389 // Throw a stack overflow exception. Guard pages will be reenabled
390 // while unwinding the stack.
391 *stub =
392 SharedRuntime::continuation_for_implicit_exception(thread,
393 pc,
394 SharedRuntime::STACK_OVERFLOW);
395 } else {
396 // Thread was in the vm or native code. Return and try to finish.
397 return true;
398 }
399 } else if (thread->in_stack_red_zone(addr)) {
400 // Fatal red zone violation. Disable the guard pages and fall through
401 // to handle_unexpected_exception way down below.
402 thread->disable_stack_red_zone();
403 tty->print_raw_cr("An irrecoverable stack overflow has occurred.");
404
405 // This is a likely cause, but hard to verify. Let's just print
406 // it as a hint.
407 tty->print_raw_cr("Please check if any of your loaded .so files has "
408 "enabled executable stack (see man page execstack(8))");
409 } else {
410 // Accessing stack address below sp may cause SEGV if current
411 // thread has MAP_GROWSDOWN stack. This should only happen when
412 // current thread was created by user code with MAP_GROWSDOWN flag
413 // and then attached to VM. See notes in os_linux.cpp.
414 if (thread->osthread()->expanding_stack() == 0) {
415 thread->osthread()->set_expanding_stack();
416 if (os::Linux::manually_expand_stack(thread, addr)) {
417 thread->osthread()->clear_expanding_stack();
418 return true;
419 }
420 thread->osthread()->clear_expanding_stack();
421 } else {
422 fatal("recursive segv. expanding stack.");
423 }
424 }
425 }
426 return false;
427 }
428
429 inline static bool checkPollingPage(address pc, address fault, address* stub) {
430 if (fault == os::get_polling_page()) {
431 *stub = SharedRuntime::get_poll_stub(pc);
432 return true;
433 }
434 return false;
435 }
436
437 inline static bool checkByteBuffer(address pc, address* stub) {
438 // BugId 4454115: A read from a MappedByteBuffer can fault
439 // here if the underlying file has been truncated.
440 // Do not crash the VM in such a case.
441 CodeBlob* cb = CodeCache::find_blob_unsafe(pc);
442 nmethod* nm = cb->is_nmethod() ? (nmethod*)cb : NULL;
443 if (nm != NULL && nm->has_unsafe_access()) {
444 *stub = StubRoutines::handler_for_unsafe_access();
445 return true;
446 }
447 return false;
448 }
449
450 inline static bool checkVerifyOops(address pc, address fault, address* stub) {
451 if (pc >= MacroAssembler::_verify_oop_implicit_branch[0]
452 && pc < MacroAssembler::_verify_oop_implicit_branch[1] ) {
453 *stub = MacroAssembler::_verify_oop_implicit_branch[2];
454 warning("fixed up memory fault in +VerifyOops at address "
455 INTPTR_FORMAT, p2i(fault));
456 return true;
457 }
458 return false;
459 }
460
461 inline static bool checkFPFault(address pc, int code,
462 JavaThread* thread, address* stub) {
463 if (code == FPE_INTDIV || code == FPE_FLTDIV) {
464 *stub =
465 SharedRuntime::
466 continuation_for_implicit_exception(thread,
467 pc,
468 SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO);
469 return true;
470 }
471 return false;
472 }
473
474 inline static bool checkNullPointer(address pc, intptr_t fault,
475 JavaThread* thread, address* stub) {
476 if (!MacroAssembler::needs_explicit_null_check(fault)) {
477 // Determination of interpreter/vtable stub/compiled code null
478 // exception
479 *stub =
480 SharedRuntime::
481 continuation_for_implicit_exception(thread, pc,
482 SharedRuntime::IMPLICIT_NULL);
483 return true;
484 }
485 return false;
486 }
487
488 inline static bool checkFastJNIAccess(address pc, address* stub) {
489 address addr = JNI_FastGetField::find_slowcase_pc(pc);
490 if (addr != (address)-1) {
491 *stub = addr;
492 return true;
493 }
494 return false;
495 }
496
497 inline static bool checkSerializePage(JavaThread* thread, address addr) {
498 return os::is_memory_serialize_page(thread, addr);
499 }
500
501 inline static bool checkZombie(sigcontext* uc, address* pc, address* stub) {
502 if (nativeInstruction_at(*pc)->is_zombie()) {
503 // zombie method (ld [%g0],%o7 instruction)
504 *stub = SharedRuntime::get_handle_wrong_method_stub();
505
506 // At the stub it needs to look like a call from the caller of this
507 // method (not a call from the segv site).
508 *pc = (address)SIG_REGS(uc).u_regs[CON_O7];
509 return true;
510 }
511 return false;
512 }
513
514 inline static bool checkICMiss(sigcontext* uc, address* pc, address* stub) {
515 #ifdef COMPILER2
516 if (nativeInstruction_at(*pc)->is_ic_miss_trap()) {
517 #ifdef ASSERT
518 #ifdef TIERED
519 CodeBlob* cb = CodeCache::find_blob_unsafe(*pc);
520 assert(cb->is_compiled_by_c2(), "Wrong compiler");
521 #endif // TIERED
522 #endif // ASSERT
523 // Inline cache missed and user trap "Tne G0+ST_RESERVED_FOR_USER_0+2" taken.
524 *stub = SharedRuntime::get_ic_miss_stub();
525 // At the stub it needs to look like a call from the caller of this
526 // method (not a call from the segv site).
527 *pc = (address)SIG_REGS(uc).u_regs[CON_O7];
528 return true;
529 }
530 #endif // COMPILER2
531 return false;
532 }
533
534 extern "C" JNIEXPORT int
535 JVM_handle_linux_signal(int sig,
536 siginfo_t* info,
537 void* ucVoid,
538 int abort_if_unrecognized) {
539 // in fact this isn't ucontext_t* at all, but struct sigcontext*
540 // but Linux porting layer uses ucontext_t, so to minimize code change
541 // we cast as needed
542 ucontext_t* ucFake = (ucontext_t*) ucVoid;
543 sigcontext* uc = (sigcontext*)ucVoid;
544
545 Thread* t = ThreadLocalStorage::get_thread_slow();
546
547 // Must do this before SignalHandlerMark, if crash protection installed we will longjmp away
548 // (no destructors can be run)
549 os::WatcherThreadCrashProtection::check_crash_protection(sig, t);
550
551 SignalHandlerMark shm(t);
552
553 // Note: it's not uncommon that JNI code uses signal/sigset to install
554 // then restore certain signal handler (e.g. to temporarily block SIGPIPE,
555 // or have a SIGILL handler when detecting CPU type). When that happens,
556 // JVM_handle_linux_signal() might be invoked with junk info/ucVoid. To
557 // avoid unnecessary crash when libjsig is not preloaded, try handle signals
558 // that do not require siginfo/ucontext first.
559
560 if (sig == SIGPIPE || sig == SIGXFSZ) {
561 // allow chained handler to go first
562 if (os::Linux::chained_handler(sig, info, ucVoid)) {
563 return true;
564 } else {
565 if (PrintMiscellaneous && (WizardMode || Verbose)) {
566 char buf[64];
567 warning("Ignoring %s - see bugs 4229104 or 646499219",
568 os::exception_name(sig, buf, sizeof(buf)));
569 }
570 return true;
571 }
572 }
573
574 JavaThread* thread = NULL;
575 VMThread* vmthread = NULL;
576 if (os::Linux::signal_handlers_are_installed) {
577 if (t != NULL ){
578 if(t->is_Java_thread()) {
579 thread = (JavaThread*)t;
580 }
581 else if(t->is_VM_thread()){
582 vmthread = (VMThread *)t;
583 }
584 }
585 }
586
587 // decide if this trap can be handled by a stub
588 address stub = NULL;
589 address pc = NULL;
590 address npc = NULL;
591
592 //%note os_trap_1
593 if (info != NULL && uc != NULL && thread != NULL) {
594 pc = address(SIG_PC(uc));
595 npc = address(SIG_NPC(uc));
596
597 // Check to see if we caught the safepoint code in the
598 // process of write protecting the memory serialization page.
599 // It write enables the page immediately after protecting it
600 // so we can just return to retry the write.
601 if ((sig == SIGSEGV) && checkSerializePage(thread, (address)info->si_addr)) {
602 // Block current thread until the memory serialize page permission restored.
603 os::block_on_serialize_page_trap();
604 return 1;
605 }
606
607 if (checkPrefetch(uc, pc)) {
608 return 1;
609 }
610
611 // Handle ALL stack overflow variations here
612 if (sig == SIGSEGV) {
613 if (checkOverflow(uc, pc, (address)info->si_addr, thread, &stub)) {
614 return 1;
615 }
616 }
617
618 if (sig == SIGBUS &&
619 thread->thread_state() == _thread_in_vm &&
620 thread->doing_unsafe_access()) {
621 stub = StubRoutines::handler_for_unsafe_access();
622 }
623
624 if (thread->thread_state() == _thread_in_Java) {
625 do {
626 // Java thread running in Java code => find exception handler if any
627 // a fault inside compiled code, the interpreter, or a stub
628
629 if ((sig == SIGSEGV) && checkPollingPage(pc, (address)info->si_addr, &stub)) {
630 break;
631 }
632
633 if ((sig == SIGBUS) && checkByteBuffer(pc, &stub)) {
634 break;
635 }
636
637 if ((sig == SIGSEGV || sig == SIGBUS) &&
638 checkVerifyOops(pc, (address)info->si_addr, &stub)) {
639 break;
640 }
641
642 if ((sig == SIGSEGV) && checkZombie(uc, &pc, &stub)) {
643 break;
644 }
645
646 if ((sig == SIGILL) && checkICMiss(uc, &pc, &stub)) {
647 break;
648 }
649
650 if ((sig == SIGFPE) && checkFPFault(pc, info->si_code, thread, &stub)) {
651 break;
652 }
653
654 if ((sig == SIGSEGV) &&
655 checkNullPointer(pc, (intptr_t)info->si_addr, thread, &stub)) {
656 break;
657 }
658 } while (0);
659
660 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in
661 // and the heap gets shrunk before the field access.
662 if ((sig == SIGSEGV) || (sig == SIGBUS)) {
663 checkFastJNIAccess(pc, &stub);
664 }
665 }
666
667 if (stub != NULL) {
668 // save all thread context in case we need to restore it
669 thread->set_saved_exception_pc(pc);
670 thread->set_saved_exception_npc(npc);
671 set_cont_address(uc, stub);
672 return true;
673 }
674 }
675
676 // signal-chaining
677 if (os::Linux::chained_handler(sig, info, ucVoid)) {
678 return true;
679 }
680
681 if (!abort_if_unrecognized) {
682 // caller wants another chance, so give it to him
683 return false;
684 }
685
686 if (pc == NULL && uc != NULL) {
687 pc = os::Linux::ucontext_get_pc((ucontext_t*)uc);
688 }
689
690 // unmask current signal
691 sigset_t newset;
692 sigemptyset(&newset);
693 sigaddset(&newset, sig);
694 sigprocmask(SIG_UNBLOCK, &newset, NULL);
695
696 VMError err(t, sig, pc, info, ucVoid);
697 err.report_and_die();
698
699 ShouldNotReachHere();
700 }
701
702 void os::Linux::init_thread_fpu_state(void) {
703 // Nothing to do
704 }
705
706 int os::Linux::get_fpu_control_word() {
707 return 0;
708 }
709
710 void os::Linux::set_fpu_control_word(int fpu) {
711 // nothing
712 }
713
714 bool os::is_allocatable(size_t bytes) {
715 #ifdef _LP64
716 return true;
717 #else
718 if (bytes < 2 * G) {
719 return true;
720 }
721
722 char* addr = reserve_memory(bytes, NULL);
723
724 if (addr != NULL) {
725 release_memory(addr, bytes);
726 }
727
728 return addr != NULL;
729 #endif // _LP64
730 }
731
732 ///////////////////////////////////////////////////////////////////////////////
733 // thread stack
734
735 size_t os::Linux::min_stack_allowed = 128 * K;
736
737 // pthread on Ubuntu is always in floating stack mode
738 bool os::Linux::supports_variable_stack_size() { return true; }
739
740 // return default stack size for thr_type
741 size_t os::Linux::default_stack_size(os::ThreadType thr_type) {
742 // default stack size (compiler thread needs larger stack)
743 size_t s = (thr_type == os::compiler_thread ? 4 * M : 1 * M);
744 return s;
745 }
746
747 size_t os::Linux::default_guard_size(os::ThreadType thr_type) {
748 // Creating guard page is very expensive. Java thread has HotSpot
749 // guard page, only enable glibc guard page for non-Java threads.
750 return (thr_type == java_thread ? 0 : page_size());
751 }
752
753 #ifndef PRODUCT
754 void os::verify_stack_alignment() {
755 }
756 #endif